两性型混凝土高效减水剂的合成与性能

以马来酸酐（MA）、烯丙基聚乙二醇（APEG,聚合度分别为7,32,45,56）和甲基酰氧乙基三甲基氯化铵（DMC）为单体,采用水溶液聚合法制备新型两性型聚羧酸系高效减水剂（APC）,并利用正交试验法优化了合成条件。探讨了单体对APC性能的影响,并对Zeta电位和混凝土力学性能进行了测试。结果表明：单体摩尔比为n（MA）∶n（APEG）∶n（DMC）=3.5∶1.5∶0.5时,APC性能最优,混凝土减水率为40%。Zeta电位测试表明空间位阻作用是APC的主要作用机理。

Synthesis and Performance of a Novel Amphoteric Superplasticizer in Concrete

A novel amphoteric polycarboxylic acid-based superplasticizer（APC）was prepared by solution copolymerization from maleic anhydride（MA）,allyl polyethylene glycol（APEG）and methacryloxyethyltrimethyl ammonium chloride（DMC）.The condition on preparation of APC was determined by the orthogonal experiment.Effect of monomers on performance of APC were investigated.Zeta potential and mechanical performances of concrete with APC were also tested.Results indicated that optimal performance of APC was obtained as the molar ratio of monomers n（MA）∶n（APEG）∶n（DMC）=3.5∶1.5∶0.5.Zeta potential measurements indicate steric repulsion between the cement particles carrying adsorbed polymer molecules is the main mechanism for dispersion.